Refrigerating apparatus



y 1967 w. K. STEINHAGEN ETAL 3,

REFRIGERAT ING APPARATUS Filed Aug. 16, 1965 3 Sheets-Sheet 1 INVENTORS William K. .Sfeinhagen Dona/d Uflgef The/r Attorney May 16, 1967 w. K. STElNHAGEN ETAL 3,339,873

REFRIGERATING APPARATUS Filed Aug. 16, 1965 5 Sheets-Sheet 2 BY Donald G. (Inger The/r Afiamey May 16, 1967 Filed Aug.

w. K. STEINHAGEN ETAL 3,

REFRIGERAT ING APPARATUS 3 Sheets-Sheet 5 Fig. 3

INVENTORS William K Sfe/hhagen BY Dana/a G.Unger Tl; air Altar/78y United States Patent 3,319,878 REFRIGERATING APPARATUS William K. Steinhagen, Royal Oak, and Donald C. Unger, Grosse Pointe Park, Mich, assignors to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Aug. 16, 1965, Ser. No. 479,754 9 Claims. (Cl. 230-186) This invention relates to compressors and more particularly to refrigerant compressors for use in bus air conditioning system or the like.

It is an object of this invention to provide a compact compressor assembly having a plurality of separate compressor units therein of the type including double-acting pistons reciprocated by means of a swashplate and including a low profile outer housing common to the individual compressor units and a belt pulley system including a single common belt for concurrently driving each of the plurality of compressor units.

A further object of the present invention is to provide a compact refrigerant compressing assembly including a plurality of separate, multiple cylinder compressor units therein each arranged within a common housing and each including a drive shaft and a drive pulley and wherein a single drive belt, driven about a fixed center, is used to concurrently rotate all the drive pulleys associated with each of the drive shafts of the separate compressor units.

A further object of the present invention is to provide a low profile refrigerant compressing assembly having high volumetric capacity by the provision of a low profile housing including a plurality of longitudinally directed cylindrical enclosures forming open-ended spaces and wherein separate multiple piston compressors are located within each of the enclosures and fluidly interrelated to have a common inlet and an outlet by means including head members for sealing the open ends of the cylindrical enclosures wherein a separate drive shaft is directed exteriorly of the common housing from each of the cornpressor units and a driven pulley connected to each one of the shafts has a continuous belt passed thereover driven about a fixed center to serve as a common drive for each of the compressor units and wherein one of the driven pulleys .has a drive bracket thereon adapted to be connected to a drive source for directing power into the belt pulley system.

Yet another object of the present invention is to reduce the size, weight and cost of a refrigerant compressing assembly suitable for association with air conditioning systems for buses or the like, by the provision of a low profile outer housing having a plurality of separate compressors supported therein and fluidly communicated to have a common inlet and outlet wherein the length of the operative assembly is reduced by the provision of a pulley operatively connected to a drive shaft of each of the separate compressor units and wherein a single drive belt is passed over all of the pulleys and located by the pulleys so that the outer periphery of the belt is generally disposed outside of the outer surface of the low profile housing and wherein the single belt is driven through a drive bracket connected to one of the pulleys.

Still another object of the present invention is to improve air conditioning systems for association with buses and the like having limited space for receiving the system by the provision of an improved refrigerant compressing assembly including a common housing having a plurality of compressor receiving enclosures therein and wherein each enclosure houses a separate compressor unit of the type having multiple cylinders and a rotatable drive shaft and wherein the common housing includes a lower sump region therein and passageway means therein for communicating the sump region with each of the separate compressor units for supplying lubricant thereto.

3,319,878 Patented May 16, 1967 Yet another object of the present invention is to improve air conditioning systems for association with buses and other equipment having limited spaces for installing air conditioning systems by the provision of an improved refrigerant compressing assembly including a common housing with a plurality of compressor receiving enclosures formed therein each housing a separate compressor that has a rotatable shaft directed exteriorly of the housing and wherein the shafts are equidistantly spaced one from the other for compactness and wherein a pulley is operatively connected to each of the shafts and a common belt is passed over the pulley for driving each of the pulleys with the pulleys defining a fixed center about which the belt is driven.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

FIGURE 1 is a view in elevation of one end of the improved refrigerant compressing assembly of the present invention.

FIGURE 2 is a view in elevation of the opposite end of the assembly shown in FIGURE 1; and

FIGURE 3 is a view in vertical section taken along the line 33 of FIGURE 1 looking in the direction of the arrows.

Referring now to the drawings, in FIGURES l and 2, a compressor assembly 19 is illustrated including an outer housing 12 having a plurality of longitudinally directed hollow cylindrical portions 14, 16, 18 wherein the outer surface of the portion 14 and the outer surface of the portion 16 are joined by a curved side surface portion 20 of the housing 12 and the housing portions 14 and 18 are joined by a curved side surface portion 22 on the opposite side of the housing 12. The housing 12 further includes a hollow base portion 24 integrally joined with the cylindrical portions 16 and 18 as best seen in FIGURE 2. The housing 12 further includes an end surface 26 at one end thereof and an end surface 28 at the opposite end thereof.

As best seen in FIGURE 3, the base portion 24 of the housing 12 forms a sump region 30 separated from the interiors of the cylindrical portions 14, 16, 18 by an interiorily located housing portion 32 directed between the end portions 26, 28 of the housing. The interior housing portion 32 serves as a bathe between the sump region 30 and an interior housing space 34 located centrally of and within the housing portions 14, 16 and 18.

Referring now more particularly to FIGURE 3, the housing portion 14 is shown in section as having a large diameter interior space 36 and an annular flange 38 at one end thereof forming a first end opening into the space 36 and an annular flange 41 at the opposite end thereof forming an opening communicating with the opposite end of the space 36. A cylinder head 39 is secured to the housing portion 14 to close the opening formed by flange 38 and a cylinder head 41 is secured to the opposite end of the housing portion 14 to close the opening formed by flange 40.

Each of the housing portions 16 and 18 has a like large diameter opening formed therein and like annular flanges at the opposite ends thereof for providing access into the interior of these housing portions. The end openings in the housing portions are closed by cylinder like heads, 39, 41 on housing portion 14.

Within each of the housing portions 14, 16, 18 and as shown in the section through the housing portion 14 as shown in FIGURE 3 is located a compressor 43 including a pair of cylinder blocks 42, 44. The cylinder block 42 has its outer end supportingly received within the annular fiange 38 and the cylinder block 44 has its outer end supportingly received by the annular flange 40. Within the cylinder block 42 is formed a cylinder bore 46 that is axially aligned with a like cylinder bore 48 within the cylinder block 44. The cylinder bores 46, 48 receive a double-ended piston member 50 to form in cooperation with the cylinder bores 46, 48 a variable volume pumping chamber at either end of the piston 50. Like cylinder bores and a piston (not shown) are located in the blocks 44, 46 at equidistant points on either side of those illustrated in a manner more specifically set forth in United States Patent Number 3,057,545, issued Oct. 9, 1962, to Ransom et al.

In the illustrated arrangement, each of the doubleended pistons including the piston 50, has a central recess 52 formed therein in which is received the outer peripheral edge of a rotatable inclined swashplate 54. The swashplate 54 has shoes 56, 58 slidably supported on either face thereof that engage balls 60, 62 respectively. The balls 60, 62 each are supported in a seat formed within the recess 52 in the double-ended piston 50.

A drive shaft 64 is directed through the head 41 on each of the housing portions 14, 16 and 18 and through the bearing blocks 42, 44 therein for relative rotation with respect thereto. The shaft 64 has a portion intermediate its ends fixedly secured to the washplate 54 whereby upon rotation of the shaft 64 the swashplate 54 will be driven in a path to cause the piston units 50 to reciprocate within the cylinder bores 46, 48 to draw refrigerant from an inlet fitting 66 in each of the heads 39 into a suction chamber 68 formed in each of the heads 39. Suitable intake valve means including a valve plate 70 and a reed valve member 72 control refrigerant fiow into the pumping chambers in each of the compressors 43.

As refrigerant is drawn into the pumping chambers formed by the cylinder bores 46, refrigerant is discharged from the pumping cylinders formed by the cylinder bores 48 through suitable discharge valve means shown in the compressor 43 in housing 14 as including a disk 72 having reed valves therein and a valve plate 74 thence into a discharge chamber 76 in the head 41 and through a crossover tube (not shown) into a discharge cavity 78 in the head 39. The discharge cavity 78 communicates with an outlet fitting 80 on each of the heads 39, as best seen in FIGURE 2. The drive shaft support details, valve details and the like are more specifically set forth in the above cited Ransom et al. patent.

These details form no part of the present invention and are merely representative of one suitable refrigerant compressor circuit for use in association with the inventive assembly. The Ransom et al. compressor is a preferred form of compressor for use in the assembly in that it is a multiple reciprocating piston compressor with a proven reliability. Moreover, its piston cylinder layout is characterized by an unusual compactness for a given compressor capacity.

The compressor unit 43 in each of the housing portions 14, 16, 18 also each include a positive displacement rotary lubricant pump assembly 90 located within a cavity 92 in each of the heads 39. The pump 90 has an impeller 94 driven olf an end extension 96 on the drive shaft 64. The details of the pump assembly 90 are more specifically shown in Ransom et al.

The assembly 90 in the compressor 43 in housing portion 14 draws lubricant upwardly through an elongated depending tube 98 that has one end thereof supported in the bearing block 42 and the opposite end thereof directed through an opening 100 in the interior housing portion 32 into the sump region 30. By virtue of this construction when the shaft 64 rotates the pump assembly 90 is operated to direct lubricant into suitable bearing components rotatably supporting the shaft 64 wthin the cylinder blocks 42, 44.

The like lubricating pump located in each of the compressors in the housing portions 16 and 18 each communicate with a shorter inclined tube 102, the one in the housing portion 16 being partially shown in FIGURE 3 as directed through the interior housing member 32 interiorly of the sump region 30 whereby lubricant can be drawn from the sump region 30 into the bearing points of the compressor 43 within each of the other housing portions 16 and 18.

The illustrated compressor in the housing portion 14 and like compressors in the housing portions 16 and 18 are set forth merely as being representative of a compact compressor of the multiple cylinder axially piston type having a limited capacity by itself but when combined with other like units has an increased refrigerant compressing capacity suitable for cooling the passenger compartment of a bus.

In the illustrated arrangement, the plural compressors are as set forth above combined in a low profile compact common housing that is readily located in the limited confines on the machine compartment of a bus or the like. The inlets 66 to the compressors 43 each communicate with an inlet manifold 104 through branch lines 106 and the outlets each communicate with a discharge manifold 108 through branch lines 109.

The manifold system illustrated in FIGURE 2 is merely representative of one suitable arrangement for fluidly communicating the multiple compressors in the common housing 12 The provision of inlets and outlets at only one end of the assembly is a desirable feature, however, in that the opposite end of the assembly can have a drive system located in close axial abutting relationship therewith to reduce the overall length of the assembly.

Another feature of the present invention that improves the compactness of the assembly 10 is the provision of a drive system 110 therein best illustrated in FIGURES 1 and 3. The drive system 110 maintains the low profile configuration of the outer housing 12 and is characterized by including a plurality of like electromagnetic clutches 112, 114, 116 operatively connected respectively to the drive shaft 64 from the compressor in the housing portion 14 and a counterpart shaft 64a and 64b associated with the compressors in the housing portions 16 and 18 respec-- tively. The electromagnetic clutches 112, 114 and 116 are are of the type more specifically set forth in United States Patent 3,082,933 issued Mar. 26, 1963, to J. A. Bernard. For purposes of the present invention, it is only necessary to point out that the clutches each include as shown in the section of the clutch 112 in FIGURE 3, a pulley 118 rotatably supported on a roller bearing assem bly 120 secured on the end of a tubular extension 122 of the end head 41 for free rotation with respect thereto. Each of the clutches further includes an energizable coil 126 that selectively attracts an armature plate 128 into frictional engagement with the rotatable pulley 118. The armature plate 128 is secured to a connecter assembly 130 that is in turn keyed to the end of the shaft 64 whereby the pulley 118 will drive the shaft 64 through the armature 128 when the coil 126 is energized to attract the armature 128 into frictional engagement with the pulley 118.

The details of the electromagnetic clutch form no part of the present invention and are merely illustrative of an arrangement for selectively energizing all or any of the compressors to vary the cooling capacity of the integrated assembly 10.

In accordance with certain other principles of the present invention, each of the pulleys 118 include an outer ring 132 thereon with straight serrations 134 formed across the width of its outer surface at circumferential so as to be driven from a single power source. In accordance with certain principles of the present invention, the drive system 110 enables a plural compressor unit assembly of the type illustrated to be closely located with respect to an output shaft on a Diesel engine or the like within a limited space since all of the pulleys and the common belt are located in a relatively narrow space on the driven end of the compressors.

More particularly, to drive the illustrated system 110 a conically shaped drive bracket adapter 140 is secured to the pulley 118 of the housing portion 16 by suitable fastening means such as screws 142 and the adapter 140 includes a threaded opening 144 therein in which one end of a drive shaft from the power unit can be secured. The unit can thereby be characterized as a drive system having a common belt driven about a fixed center by a shaft offset with respect to the fixed center about which the belt drives.

The arrangement is in addition to being unusually compact includes the further feature of providing positive drive to each of the pulleys of the electromagnetic clutches 112, 114, 116 whereby there is an even transfer of power from the drive motor to each of the compressors whereby the compressors are operated at the same speed to effect a like compressor of a suitable refrigerant to produce the desired high capacity cooling from the compact assembly.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In a plural compressor assembly the combination of, a plurality of compressor units, each of said compressor units having a cylinder block including a plurality of cylinder bores therein, pistons in each of said cylinder bores, a rotatable shaft in each of said blocks, and means connecting said pistons in each of said blocks to one of said shafts for producing reciprocating movement of said pistons within said cylinder bores, a housing common to each of said plurality of compressor units including a plurality of open-ended axial spaces therethrough, each of said spaces having one of said cylinder blocks sup ported therein, a head member closing each of the open ends of said spaces in said housing, an inlet and an outlet in each of said heads at only one end of said housing, means including valve means in said heads for directing fiuid from each of said inlets interiorly of said cylinders and for directing fluid from said cylinders to said outlets upon reciprocation of said pistons, each of said shafts having an end directed exteriorly of said housing, a pulley on each of said shafts, a continuous drive belt directed over each of said pulleys about a fixed center belt drive system, and means connected directly to one of said pulleys adapted to be operatively connected to a power source for rotating said one of said pulleys, said continuous belt being driven upon rotation of said one of said pulleys to concurrently drive the other of said pulleys.

2. In the combination of claim 1, said housing spaces having the longitudinal axes thereof spaced equidistant with respect to one another for reducing the outer dimensional configuration of said outer housing.

3. In the combination of claim 1, said common housing having a base portion thereon forming a lubricant sump region disposed below each of said compressor units, a plurality of depending tubular members, each of said depending tubular members having one end thereof disposed within said sump region and the other end thereof directed through a portion of the cylinder block of one of said compressor units for communicating said compressor units with said sump region.

4. In a compressor assembly the combination of an outer housing having a plurality of open-ended spaces directed axially therethrough, a cylinder block located in each of said open-ended spaces, coacting means on said cylinder block and said housing for supporting each of said cylinder blocks, each of said cylinder blocks including a plurality of cylinder bores therein, a piston sildably supported in each of said cylinder bores for reciprocable movement relative thereto, a rotatable shaft directed interiorly of each of said cylinder blocks, each of said shafts having a portion thereof rotatably supported by said cylinder blocks, means for connecting each of said pistons to one of said shafts for producing reciprocable movement of said pistons within said cylinder bores upon rotation of said shaft, magnetic clutch means secured to each of said shafts including a pulley member selectively connected to said shaft for rotation therewith, a continuous belt passed over the outer periphery of each of said pulley members, said belt having a fixed center of rotation, and means on one of said pulleys offset with respect to said fixed center of rotation of said belt adapted to be connected to a power source for concurrently driving each of said pulleys through said continuous fixed center belt.

5. In the combination of claim 4, each of said pulleys having a plurality of serrations formed circumferentially about the outer periphery thereof, said continuous drive belt having a plurality of transverse cogs therein received by said serrations for preventing relative slippage between said continuous drive belt and each of said pulleys whereby said continuous belt can be driven through rotation of one of said pulleys to effect concurrent rotation of all of said pulleys.

6. A high capacity low-cost compressor assembly com- PI'lSlHg a common housing having a plurality of longitudinally directed cylindrical enclosures each forming an open-ended space, said housing including a sump enclosure disposed beneath said longitudinally directed enclosures, passageway means in said housing communicating each of said open-ended spaces with the interior of sad sump enclosure, a cylinder block located in each of said open-ended spaces having portions thereon sup ported by said housing, each of said cylinder blocks having a plurality of spaced apart axially aligned pumping chambers formed therein, a first plurality of cylinder heads supported on said housing for closing one of the open ends of each of said longitudinally directed cylindrical enclosures, a second plurality of cylinder heads supported on said housing for closing the opposite open ends of said longitudinally directed cylindrical enclosures, an inlet and an outlet fitting on each of said first plurality of cylinder heads, first fluid flow passageway means in said first plurality of cylinder heads for communicating said inlet and outlet fittings with certain ones of said pumping chambers in said cylinder block, second fluid flow passageway means in said second plurality of cylinder heads, means for intercommunicating said first fluid flow passageways with said second fluid flow passageways for selectively connecting other of said pumping chambers in said cylinder block with said inlet and said outlet fittings, means for reciprocating said piston means within said pumping chambers including a longitudinally directed shaft directed from interiorly of each of said cylinder blocks through one of said second plurality of cylinder heads exteriorly of said common housing, a plurality of pulleys, means for rotatably supporting one of said pulleys on each of said second plurality of cylinder heads, magnetic clutch means for selectively operatively connecting said pulleys to each of said drive shafts, a continuous drive belt directed over each of said pulleys, said belt having a fixed center of rotation formed by said pulleys, a drive connection secured to one of said pulleys on the outer face thereof for operatively connecting said one of said pulleys to a power source, said drive member on one of said pulleys being rotatable about the axis of rotation of said one of said pulleys to drive said belt to cause concurrent rotation of each of said pulleys by directing said belt continuously about its fixed center of rotation.

7. In the combination of claim 6, said drive shafts being located equidistant from one another, said plurality of pulleys locating said belt to travel through a generally triangular path, said belt having the outer peripheral surface thereof located outwardly of the outer surface of each of said longitudinally directed cylindrical enclosures.

8. A plurality of pumping units, each of said pumping units including a pumping chamber having an inlet and an outlet, piston means in each of said pumping chamber-s, means for controlling fluid flow from said inlet into said pumping chamber and from said pumping chamber through said outlet upon movement of said piston means in said pumping chamber, a common housing enclosing each of said pumping units and supporting each of said pumping units in spaced relationship With one another, a drive shaft connected to each of said piston means having one end thereof directed exteriorly of said common housing, said drive shafts being arranged in spaced parallelism with one another and being spaced apart an equidistance, a drive pulley concentrically arranged about each of said drive shafts, means for connecting each of said pulleys to said drive shaft, a continuous drive belt directed over each of said pulleys, said pulleys defining a fixed center of rotation for said drive belt, and means on one of said pulleys for rotating said one of said pulleys to cause said belt to pass over all of said pulleys whereby each of said drive shafts is operated to produce movement of said piston means in said pumping chambers.

9. In the combination of claim 8, said common housing including a plurality of longitudinally directed cylindrical enclosures forming spaces for receiving each of said pumping units, said cylindrical enclosures having the outer surfaces thereof disposed within the outer peripheral surface of said drive belt.

References Cited by the Examiner UNITED STATES PATENTS 1,660,524 2/1928 Fodnar 23015 2,185,338 1/1940 Hassler 230158 2,309,443 1/1943 Cuthbert 230-158 2,595,098 4/1952 *Poglay 230- 38 2,866,528 12/1958 Jacobs 23O15 3,057,545 10/1962 Ransom et al 230-186 3,082,933 3/1963 Bernard 23015 3,215,341 11/1965 Francis 230186 3,220,211 11/1965 Nordquest 230-186 DONLEY J. STOCKING, Primary Examiner.

W. J. KRAUSS, Assistant Examiner. 

1. IN A PLURAL COMPRESSOR ASSEMBLY THE COMBINATION OF, A PLURALITY OF COMPRESSOR UNITS, EACH OF SAID COMPRESSOR UNITS HAVING A CYLINDER BLOCK INCLUDING A PLURALITY OF CYLINDER BORES THEREIN, PISTONS IN EACH OF SAID CYLINDER BORES, A ROTATABLE SHAFT IN EACH OF SAID BLOCKS, AND MEANS CONNECTING SAID PISTONS IN EACH OF SAID BLOCKS TO ONE OF SAID SHAFTS FOR PRODUCING RECIPROCATING MOVEMENT OF SAID PISTONS WITHIN SAID CYLINDER BORES, A HOUSING COMMON TO EACH OF SAID PLURALITY OF COMPRESSOR UNITS INCLUDING A PLURALITY OF OPEN-ENDED AXIAL SPACES THERETHROUGH, EACH OF SAID SPACES HAVING ONE OF SAID CYLINDER BLOCKS SUPPORTED THEREIN, A HEAD MEMBER CLOSING EACH OF THE OPEN ENDS OF SAID SPACES IN SAID HOUSING, AN INLET AND AN OUTLET IN EACH OF SAID HEADS AT ONLY ONE END OF SAID HOUSING, 